提出了一种非侵入式同时测量气固两相流型和电荷分布的可视化测试方法。数值仿真结果表明,ECT提供的介电常数分布信息可用于修正实际流型下的EST电荷灵敏场,降低了电荷分布反演的不确定性,EST的图像重建误差有所减小,有效的提高了电荷分布反演的精度。将该测试方法分别应用于粉体重力输送系统和高压密相气力输送系统,结果表明重力输送试验中颗粒浓度大的区域电荷密度值较大,而在气力输送试验中,颗粒浓度大的区域,电荷密度值反而较小,且随着管内煤粉颗粒浓度的增加,粉体总的电荷强度值减小。
In this paper, a non-invasive measurement method is proposed, which can visualize the flow pattern and charge distribution of gas-solid two-phase flow. Numerical simulation shows that the permittivity distribution acquired from ECT (Electrical Capacitance Tomography) can be used to improve the accuracy for identifying charge sensitivity field of EST (Electrostatic Tomography) and to reduce the uncertainty of inverse calculation of charge distribution, which effectively reduces the error in image reconstruction, so that the accuracy of inversion charge distribution calculation can be significantly improved. This method has been applied to flow measurement in a gravity-dropping conveyance system and a pneumatic conveyance system and the experimental results show that, for the gravity-dropping system, charge density increases with particle concentration, whilst in the pneumatic conveyance system, charge density decreases in the The total charge intensity decreases with the increase area where the particle concentration is higher of the concentration of pulverized coal in the pipe